Question

D. Write 'True' or 'False': -
1) Goitre is found due to deficiency of Iodine.
2) Sodium hydroxide is a weak base. T
3) PH change is the cause of tooth decay. F
4) Ions are formed by the loss or gain of electrons.
5) Protons are negatively charged particles.
6) Distance is a vector quantity.
7) Rate of change of displacement is velocity.​

Answer 1

Answer:

1) Goitre is found due to deficiency of Iodine. TRUE

2) Sodium hydroxide is a weak base. FALSE

3) PH change is the cause of tooth decay. TRUE

4) Ions are formed by the loss or gain of electrons. TRUE

5) Protons are negatively charged particles. FALSE

6) Distance is a vector quantity. FALSE

7) Rate of change of displacement is velocity. TRUE

EXPLANATION:

1. Goitre is a disorder due to deficiency of iodine in the hormone thyroxine. It causes inflammation of thyroid gland.

2.Sodium hydroxide, NaOH is a strong base. Strong base is one that replaces hydroxide ion easily .

3. When the pH of mouth falls below 5.5 , it causes decay of tooth. The change of pH is due to the activity of bacteria residing within mouth.

4.When an atom loses electron, it becomes positively charged ion called cation. When the atom gains electron, it becomes negatively charged ion called anion.

5.Protons present inside the nucleus of atom is positively charged. The negatively charged particles are electrons. Neutrons contain no charge.

6.Distance is a scalar quantity. It has only magnitude and no direction. It cannot be negative.

7.Rate of change of displacement is called velocity. Both displacement and velocity are vector quantities. They have both magnitude and direction.

Answer 2

Hi there! Hope this helps.

Answer:

1. True

2.False

3. True

4.True

5.False

6.False

7.True